Atticus and Walter Cunningham Jr. discuss farming at lunch.

Scout starts a fight with Walter after he gets her off on the wrong foot because she got in trouble at school.  Jem pulls her off and invites Walter over for lunch.

Atticus is also home, and he seems to enjoy discussing farm matters with Walter over lunch.

While Walter piled food on his plate, he and Atticus talked together like two men, to the wonderment of Jem and me. Atticus was expounding upon farm problems when Walter interrupted to ask if there was any molasses in the house. (ch 3)

Next Scout gets in trouble for asking Walter why he was pouring molasses over his food, which kind of dampens the spirit of the party.  Walter feels ashamed of his social blunder, and Cal tells Scout that Walter is her company and should be allowed to do whatever he wants.

Walter is a very mature and polite young man.  In a complete contrast to the Ewell family, the Cunningham's are proud and won't accept charity.  Walter is very respectful and proves himself to be a very good guest, and able to carry on a conversation like an adult.